A tumor after an insect bite is a fairly common phenomenon. Sometimes it even occurs in response to attacks by seemingly completely harmless creatures, such as small flies and mosquitoes. And after being stung by wasps, bees, hornets, bumblebees, some ichneumon wasps and predatory bugs, tumors appear in almost every person, and can often reach impressive sizes.

The reason a tumor appears in response is an active response immune system the body to enzymes and toxins introduced by insects under the skin. During the inflammatory process, lymph accumulates in soft tissues, which causes a natural increase in their volume.

But wasps, hornets and bees, when attacked, inject a hefty dose of poison under the skin, which can destroy the cell walls of tissues and initiate severe inflammation, often accompanied by an allergic reaction. Depending on the strength of a person's immune response, the tumor can be either small or very extensive, up to swelling of an entire limb or large part of the body.

On a note

When talking about insect bites, many people also mean attacks from other arthropods: spiders, scolopendras, scorpions and ticks, which, generally speaking, do not belong to the order Insects (insects have only 3 pairs of legs).

A tumor as a normal reaction of the body to a bite

If your leg, arm or cheek is slightly swollen from an insect bite, then before you panic and talk about a “terrible allergy”, you should consider that minor swelling and swelling is a completely normal reaction healthy body against the ingress of foreign biologically active substances into it.

The venom of most stinging insects (and poisonous spiders) contains a group of substances that cause the destruction of cells and the leakage of their contents into the intercellular space. The affected person’s body regards the insect’s toxins and the contents of damaged cells as substances dangerous to it and attacks them. In addition, their presence in the intercellular space is harmful and can lead to metabolic disorders in tissues.

The venom of hornets, wasps and some spiders, among other things, also causes destruction of the walls of small blood vessels, which often leads to subcutaneous bleeding, and in especially dangerous cases (with massive bites) – to internal bleeding.

The photo shows a tumor after a hornet bite:

Blood begins to actively flow into the damaged area, and in addition to this, the volume of intercellular fluid increases. Under such conditions, it is easier for the body to mobilize its resources to neutralize the poison.

So, minor swelling or edema as a result of an attack by some arthropod is the norm, so there is no need to worry too much in such cases. It’s another matter when, from an insect bite, the entire or significant part of a leg, arm, face is swollen, or the swelling begins to spread throughout the body.

This is already an excessive reaction, often a sign of the development of a dangerous allergy. Such tumors and edema, of course, should be dealt with as soon as possible.

Typical symptoms that appear after arthropod attacks include the following:

Often, at the site of the bite, the victim’s temperature rises and a burning sensation is felt - this is also normal. The alarm should be sounded when a general and strong increase in body temperature occurs - this is already a signal that the process is becoming generalized, and the patient may need to be hospitalized.

Talking about possible consequences, we should not forget that in the same person, an insect bite of the same species can cause varying degrees and the nature of symptoms. This largely depends on where the bite occurred. For example, an insect bite on the eyelid sometimes leads to complete swelling of half the face and the closing of the eye, while at the same time a lump on the back or wrist will cause much less unpleasant consequences.

“We were very scared when my husband’s leg became swollen after an insect bite. It turned out that this is a little water scorpion; it lives in all ponds and crawls along the bottom. The husband thought that he had stepped on a branch and special attention didn’t, and then he started to feel sick. When he came out of the lake, his leg was already swollen, and then severe redness and swelling appeared, the whole leg began to look like a barrel. We became truly scared. At the same time, he says that there is no particular pain, only at the site of the bite. I nevertheless persuaded him to go to the hospital; I was driving myself. The doctor told us that such severe swelling from an insect bite is rare, especially from a water scorpion. This swelling persisted for a couple more days, and bruises appeared in several places. After about a week, the swelling completely subsided, but in general it did not interfere with Andrey’s ability to walk and swim normally.”

Svetlana, Chelyabinsk

When should a tumor be treated?

In some cases, the degree of tumor manifestation from an insect bite is excessive and requires treatment. Such situations include:

• allergic tumors and edema;
• tumors affecting internal organs or the respiratory system;
• inflammation that occurs in response to the introduction of a secondary infection into the bite wound.

• an insect bite becomes inflamed after a few days - this is a clear sign of infection of the wound;
• the swelling is spreading more and more, rashes and blisters appear in different parts of the body from an insect bite;
• signs of general intoxication of the body appear: dizziness, abdominal pain, nausea, fever;
• a large abscess appears at the site of the insect bite (the formation of pus is a consequence of tissue damage);
• from an insect bite, the eye, tongue or larynx is swollen - in the first case there is a risk of serious damage to the eye, in the last two - suffocation can occur.

In all of these cases, it is necessary to take into account that first aid can only serve to alleviate the condition of the victim before visiting a doctor. You should not turn such help into long-term self-medication.

“I don’t even know what to do. Two days ago I was bitten by some small wasp, and there is still a red spot at the site of the bite that is very itchy and painful. It doesn’t seem to be spreading, but this nasty insect bit me exactly where the waistband of my trousers was, and now it’s very uncomfortable to wear it. Immediately after that there was still nothing, and then it just swollen and has remained unchanged for the third day. Tell me, do we need to fight this somehow or wait until it goes away on its own?”

Oksana, Mozhaisk

Anti-inflammatory drugs

As a rule, special gels, creams and ointments for insect bites are used to treat swelling and developed inflammation. The most popular of them include:

• Fenistil;
• Levomekol;
• Advantan;
• Flucinar;

With these remedies, inflammation from an insect bite can be smeared on your own, without a doctor’s prescription, taking into account only contraindications to a specific drug. As for anti-inflammatory drugs taken orally, they should be prescribed exclusively by a doctor - self-administration of such drugs (steroidal and non-steroidal) can cause significant harm to the body.

In addition to pharmaceuticals, there is also a whole range of traditional medicine designed to help the victim. If, for example, a leg or arm is swollen due to an insect bite, you can use the following folk remedies:

• plantain leaf juice;
• parsley leaves crushed into pulp;
• aloe leaves;
• calendula tincture.

The main disadvantage of folk remedies is their relatively low effectiveness: if the tumor is small, then there is little point in treating it, but if a generalized reaction has begun, then plantain juice and calendula, alas, will not help.

As a rule, folk remedies are used only to reduce pain at the site of the bite, without placing any burden on them great hopes regarding tumor removal.

Instructions for treating tumors after insect bites

Depending on how much time has passed since the bite, treatment can be carried out using different means. So, if the tumor has just begun to appear, it will be enough to apply a cold compress to it(it will narrow the blood vessels and also reduce the rate of absorption of the poison into the blood).

Such help is especially relevant when an insect bites the eye - one compress in this situation may be enough to avoid losing vision due to a tumor for a couple of days.

While the area damaged by the insect hurts and the tumor increases in size, you should not neglect, for example, Soventol or Fenistil - these drugs have an antihistamine effect, preventing the development of an allergic reaction.

If you notice that a tumor or swelling from an insect bite is beginning to dangerously spread to more and more areas of the body, you should immediately call Ambulance and get advice by phone. Often in such cases, doctors recommend taking antihistamines (Diphenhydramine or Suprastin). It’s even better not to delay and take the victim to the hospital, or call doctors at home - after all, it is possible that after a while the situation may become critical...

Also, in no case should you hesitate when localizing tumors and swelling in vital places - for example, on the throat. If a cold compress does not help, then you need to call an ambulance, as continued swelling of the airways can eventually lead to their complete closure.

Specifics of inflammation in different parts of the body

According to statistics, most often stinging insect bites occur on human limbs. If a leg or arm is swollen from such a bite, the situation is, of course, unpleasant, but quite tolerable, although the injured limb may even take on a frightening appearance.

“Last summer I was bitten by some insect, my hand became terribly swollen, so much so that I could not move my fingers. It seems like nothing unusual, but it’s really scary that it won’t stay like this forever. I walked around with this pillow for about a week, and then it gradually went away. Although after the bite there was a lump on the back of the hand that remained for a couple of weeks.”

Yaroslav, Ramenskoye

A much more serious situation is when, for example, a hornet or wasp stings the eye, eyelid, lip or tongue. A tumor after such a bite prevents a person from living fully, receiving information from the outside world, and speaking. In addition, some symptoms that appear after such an attack can seriously threaten the health, and sometimes the life of the victim.

“It was scary when a bee bit me in the eye. This guy walks around the garden, and half of his face is swollen like a ball, and even turned a little blue. We showed it to the doctor, he said that we were lucky and it’s okay, it will go away on its own. Now the eyelid seems to be opening a little, but yesterday I couldn’t even move it.”

Alexander, Vladimir

In conclusion, I would like to once again draw attention to the fact that if, as a result of an insect bite, symptoms of general poisoning appear, a rash all over the body, shortness of breath, nausea or extensive swelling, the victim should be taken to the hospital. Even a single bee sting can in some cases cause severe allergic reactions and lead to anaphylactic shock.

You can never know for sure exactly how the body will react to the poison that has entered it, and if you are too careless, you may not even have time to call an ambulance. Therefore, after a bite, carefully monitor your condition or the condition of a loved one, and if the first alarming symptoms appear, call the hospital.

Useful video about different reactions to insect bites: from swelling to anaphylactic shock

What can be done to protect against insect bites and what products to use in case of an allergic reaction

The length of everything is measured in inches or feet. Feet is a plural form of foot, which is not a unit of length in the Imperial and American measurement systems. However, when describing an architectural space - a rectangle or a square - the area must be calculated using two dimensions, since area is a two-dimensional dimension. The area of ​​a room is calculated by multiplying the length and width of the room in feet. For example, if a room is 15 feet long and 12 feet wide, then the area of ​​the room is 15 times 12, which is 180 square feet.

Difference between feet and square feet

Foot Fundamentals Vs. Square foot

Legs ( plural foot) is a non-SI unit for measuring length as specified in Imperial and American units. It is used to measure height, length and distance. The square foot is a non-SI unit for measuring area, primarily in the United States. It is the plural of square foot, used to measure any two-dimensional space.

Symbol and calculation of feet Vs. Square foot

The international symbol for feet is "feet", while square feet are symbolized as "sq ft." Or "ft 2". The area of ​​a rectangular or square room is calculated in square feet by multiplying the length and width of the room in feet. If the room is 12 feet long and 12 feet wide, then the area of ​​the room is (12 * 12) 144 sq.

Leg Transformation Vs. Square foot

1 foot converts to 12 inches or 0.3048 meters. Likewise, 1 square meter is equivalent to 0.092903 square meters or 144 square inches. Area of ​​1 sq. Feet would be 12*12 inches square. Feet is a one-dimensional unit, and square feet is a two-dimensional unit for an area.

Examples of feet Vs. Square foot

If a room measures 15 feet long and 10 feet wide, then the area of ​​the room is calculated as:

Area = 15 x 10 = 150 square feet or 150 sq. ft or 150 ft 2

Feet vs. Square Feet: Comparison Chart

Summary of feet and square feet

When you measure the length of anything, it is measured in inches or feet, but area is a two-dimensional dimension, so it is calculated in two dimensions - length and width. To calculate architectural space in square feet, length and width are measured in feet and then multiplied together to give area in square feet or ft2. Foot is a non-SI unit for measuring length, whereas square foot is unit of measure unit of measurement other than SI.

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1 square meter [m²] = 10.7638673611111 sq. ft (US survey) [ft²]

Initial value

Converted value

square meter square kilometer square hectometer square decameter square decimeter square centimeter square millimeter square micrometer square nanometer hectare ar barn square mile sq. mile (US, surveyor) square yard square foot² sq. foot (USA, surveyor) square inch circular inch township section acre acre (USA, surveyor) ore square chain square rod rod² (USA, surveyor) square perch square rod sq. thousandth circular mil homestead sabin arpan cuerda square castilian cubit varas conuqueras cuad cross section of electron tithe (government) tithe economic round square verst square arshin square foot square fathom square inch (Russian) square line Planck area

More about the area

General information

Area is a quantity geometric figure in two-dimensional space. It is used in mathematics, medicine, engineering and other sciences, for example in calculating the cross-section of cells, atoms, or pipes such as blood vessels or water pipes. In geography, area is used to compare the sizes of cities, lakes, countries, and other geographic features. Population density calculations also use area. Population density is defined as the number of people per unit area.

Units

Square meters

Area is measured in SI units in square meters. One square meter is the area of ​​a square with a side of one meter.

Unit square

A unit square is a square with sides of one unit. The area of ​​a unit square is also equal to one. In a rectangular coordinate system, this square is located at coordinates (0,0), (0,1), (1,0) and (1,1). On the complex plane the coordinates are 0, 1, i And i+1, where i- imaginary number.

Ar

Ar or weaving, as a measure of area, is used in the CIS countries, Indonesia and some other European countries, to measure small urban objects such as parks when a hectare is too large. One are is equal to 100 square meters. In some countries this unit is called differently.

Hectare

Real estate, especially land, is measured in hectares. One hectare is equal to 10,000 square meters. It has been used since French Revolution, and is used in European Union and some other regions. Just like the macaw, in some countries the hectare is called differently.

Acre

IN North America and Burma, area is measured in acres. The hectares are not used there. One acre is equal to 4046.86 square meters. An acre was originally defined as the area that a farmer with a team of two oxen could plow in one day.

Barn

Barns are used in nuclear physics to measure the cross section of atoms. One barn is equal to 10⁻²⁸ square meters. The barn is not a unit in the SI system, but is accepted for use in this system. One barn approximately equal to area cross-section of a uranium nucleus, which physicists jokingly called “as huge as a barn.” Barn in English is “barn” (pronounced barn) and from a joke among physicists this word became the name of a unit of area. This unit originated during World War II, and was liked by scientists because its name could be used as a code in correspondence and telephone conversations as part of the Manhattan Project.

Area calculation

The area of ​​the simplest geometric figures is found by comparing them with the square of a known area. This is convenient because the area of ​​the square is easy to calculate. Some formulas for calculating the area of ​​geometric figures given below were obtained in this way. Also, to calculate the area, especially of a polygon, the figure is divided into triangles, the area of ​​each triangle is calculated using the formula, and then added. The area of ​​more complex figures is calculated using mathematical analysis.

Formulas for calculating area

• Square: square side.
• Rectangle: product of the parties.
• Triangle (side and height known): the product of the side and the height (the distance from that side to the edge), divided in half. Formula: A = ½ah, Where A- square, a- side, and h- height.
• Triangle (two sides and the angle between them are known): the product of the sides and the sine of the angle between them, divided in half. Formula: A = ½ab sin(α), where A- square, a And b- sides, and α - the angle between them.
• Equilateral triangle: side squared divided by 4 and multiplied by Square root out of three.
• Parallelogram: the product of a side and the height measured from that side to the opposite side.
• Trapezoid: the sum of two parallel sides multiplied by the height and divided by two. The height is measured between these two sides.
• Circle: the product of the square of the radius and π.
• Ellipse: product of semi-axes and π.

Surface Area Calculation

You can find the surface area of ​​simple volumetric figures, such as prisms, by unfolding this figure on a plane. It is impossible to obtain a development of the ball in this way. The surface area of ​​a sphere is found using the formula by multiplying the square of the radius by 4π. From this formula it follows that the area of ​​a circle is four times less than the surface area of ​​a ball with the same radius.

Surface areas of some astronomical objects: Sun - 6,088 x 10¹² square kilometers; Earth - 5.1 x 10⁸; thus, the surface area of ​​the Earth is approximately 12 times smaller than the surface area of ​​the Sun. The Moon's surface area is approximately 3.793 x 10⁷ square kilometers, which is about 13 times smaller than the Earth's surface area.

Planimeter

The area can also be calculated using a special device - a planimeter. There are several types of this device, for example polar and linear. Also, planimeters can be analog and digital. In addition to other functions, digital planimeters can be scaled, making it easier to measure features on a map. The planimeter measures the distance traveled around the perimeter of the object being measured, as well as the direction. The distance traveled by the planimeter parallel to its axis is not measured. These devices are used in medicine, biology, technology, and agriculture.

Theorem on properties of areas

According to the isoperimetric theorem, of all figures with the same perimeter, the most big square at the circle. If, on the contrary, we compare figures with the same area, then the circle has the smallest perimeter. The perimeter is the sum of the lengths of the sides of a geometric figure, or the line that marks the boundaries of this figure.

Geographical features with the largest area

Country: Russia, 17,098,242 square kilometers, including land and water. The second and third largest countries by area are Canada and China.

City: New York is the city with the largest area of ​​8683 square kilometers. The second largest city by area is Tokyo, occupying 6993 square kilometers. The third is Chicago, with an area of ​​5,498 square kilometers.

City Square: The largest square, covering 1 square kilometer, is located in the capital of Indonesia, Jakarta. This is Medan Merdeka Square. Second largest area at 0.57 square kilometer- Praça doz Girascoes in the city of Palmas, Brazil. The third largest is Tiananmen Square in China, 0.44 square kilometers.

Lake: Geographers debate whether the Caspian Sea is a lake, but if so, it is the largest lake in the world with an area of ​​371,000 square kilometers. The second largest lake by area is Lake Superior in North America. It is one of the lakes of the Great Lakes system; its area is 82,414 square kilometers. The third largest lake in Africa is Lake Victoria. It covers an area of ​​69,485 square kilometers.

Length and distance converter Mass converter Converter of volume measures of bulk products and food products Area converter Converter of volume and units of measurement in culinary recipes Temperature converter Converter of pressure, mechanical stress, Young's modulus Converter of energy and work Converter of power Converter of force Converter of time Linear speed converter Flat angle Converter thermal efficiency and fuel efficiency Converter of numbers in various number systems Converter of units of measurement of quantity of information Currency rates Women's clothing and shoe sizes Men's clothing and shoe sizes Angular velocity and rotation frequency converter Acceleration converter Angular acceleration converter Density converter Specific volume converter Moment of inertia converter Moment of force converter Torque converter Specific heat of combustion converter (by mass) Energy density and specific heat of combustion converter (by volume) Temperature difference converter Coefficient of thermal expansion converter Thermal resistance converter Thermal conductivity converter Specific heat capacity converter Energy exposure and thermal radiation power converter Heat flux density converter Heat transfer coefficient converter Volume flow rate converter Mass flow rate converter Molar flow rate converter Mass flow density converter Molar concentration converter Mass concentration in solution converter Dynamic (absolute) viscosity converter Kinematic viscosity converter Surface tension converter Vapor permeability converter Water vapor flow density converter Sound level converter Microphone sensitivity converter Converter Sound Pressure Level (SPL) Sound Pressure Level Converter with Selectable Reference Pressure Luminance Converter Luminous Intensity Converter Illuminance Converter Computer Graphics Resolution Converter Frequency and Wavelength Converter Diopter Power and Focal Length Diopter Power and Lens Magnification (×) Converter electric charge Linear charge density converter Surface charge density converter Volume charge density converter Electric current converter Linear current density converter Surface current density converter Electric field strength converter Electrostatic potential and voltage converter Electrical resistance converter Electrical resistivity converter Electrical conductivity converter Electrical conductivity converter Electrical capacitance Inductance Converter American Wire Gauge Converter Levels in dBm (dBm or dBm), dBV (dBV), watts, etc. units Magnetomotive force converter Magnetic field strength converter Magnetic flux converter Magnetic induction converter Radiation. Ionizing radiation absorbed dose rate converter Radioactivity. Radioactive decay converter Radiation. Exposure dose converter Radiation. Absorbed dose converter Decimal prefix converter Data transfer Typography and image processing unit converter Timber volume unit converter Calculation of molar mass Periodic table of chemical elements by D. I. Mendeleev

1 square meter [m²] = 10.7638673611111 sq. ft (US survey) [ft²]

Initial value

Converted value

square meter square kilometer square hectometer square decameter square decimeter square centimeter square millimeter square micrometer square nanometer hectare ar barn square mile sq. mile (US, surveyor) square yard square foot² sq. foot (USA, surveyor) square inch circular inch township section acre acre (USA, surveyor) ore square chain square rod rod² (USA, surveyor) square perch square rod sq. thousandth circular mil homestead sabin arpan cuerda square castilian cubit varas conuqueras cuad cross section of electron tithe (government) tithe economic round square verst square arshin square foot square fathom square inch (Russian) square line Planck area

More about the area

General information

Area is the size of a geometric figure in two-dimensional space. It is used in mathematics, medicine, engineering and other sciences, for example in calculating the cross-section of cells, atoms, or pipes such as blood vessels or water pipes. In geography, area is used to compare the sizes of cities, lakes, countries, and other geographic features. Population density calculations also use area. Population density is defined as the number of people per unit area.

Units

Square meters

Area is measured in SI units in square meters. One square meter is the area of ​​a square with a side of one meter.

Unit square

A unit square is a square with sides of one unit. The area of ​​a unit square is also equal to one. In a rectangular coordinate system, this square is located at coordinates (0,0), (0,1), (1,0) and (1,1). On the complex plane the coordinates are 0, 1, i And i+1, where i- imaginary number.

Ar

Ar or weaving, as a measure of area, is used in the CIS countries, Indonesia and some other European countries, to measure small urban objects such as parks when a hectare is too large. One are is equal to 100 square meters. In some countries this unit is called differently.

Hectare

Real estate, especially land, is measured in hectares. One hectare is equal to 10,000 square meters. It has been in use since the French Revolution, and is used in the European Union and some other regions. Just like the macaw, in some countries the hectare is called differently.

Acre

In North America and Burma, area is measured in acres. The hectares are not used there. One acre is equal to 4046.86 square meters. An acre was originally defined as the area that a farmer with a team of two oxen could plow in one day.

Barn

Barns are used in nuclear physics to measure the cross section of atoms. One barn is equal to 10⁻²⁸ square meters. The barn is not a unit in the SI system, but is accepted for use in this system. One barn is approximately equal to the cross-sectional area of ​​a uranium nucleus, which physicists jokingly called “as huge as a barn.” Barn in English is “barn” (pronounced barn) and from a joke among physicists this word became the name of a unit of area. This unit originated during World War II, and was liked by scientists because its name could be used as a code in correspondence and telephone conversations within the Manhattan Project.

Area calculation

The area of ​​the simplest geometric figures is found by comparing them with the square of a known area. This is convenient because the area of ​​the square is easy to calculate. Some formulas for calculating the area of ​​geometric figures given below were obtained in this way. Also, to calculate the area, especially of a polygon, the figure is divided into triangles, the area of ​​each triangle is calculated using the formula, and then added. The area of ​​more complex figures is calculated using mathematical analysis.

Formulas for calculating area

• Square: square side.
• Rectangle: product of the parties.
• Triangle (side and height known): the product of the side and the height (the distance from that side to the edge), divided in half. Formula: A = ½ah, Where A- square, a- side, and h- height.
• Triangle (two sides and the angle between them are known): the product of the sides and the sine of the angle between them, divided in half. Formula: A = ½ab sin(α), where A- square, a And b- sides, and α - the angle between them.
• Equilateral triangle: side squared divided by 4 and multiplied by the square root of three.
• Parallelogram: the product of a side and the height measured from that side to the opposite side.
• Trapezoid: the sum of two parallel sides multiplied by the height and divided by two. The height is measured between these two sides.
• Circle: the product of the square of the radius and π.
• Ellipse: product of semi-axes and π.

Surface Area Calculation

You can find the surface area of ​​simple volumetric figures, such as prisms, by unfolding this figure on a plane. It is impossible to obtain a development of the ball in this way. The surface area of ​​a sphere is found using the formula by multiplying the square of the radius by 4π. From this formula it follows that the area of ​​a circle is four times less than the surface area of ​​a ball with the same radius.

Surface areas of some astronomical objects: Sun - 6,088 x 10¹² square kilometers; Earth - 5.1 x 10⁸; thus, the surface area of ​​the Earth is approximately 12 times smaller than the surface area of ​​the Sun. The Moon's surface area is approximately 3.793 x 10⁷ square kilometers, which is about 13 times smaller than the Earth's surface area.

Planimeter

The area can also be calculated using a special device - a planimeter. There are several types of this device, for example polar and linear. Also, planimeters can be analog and digital. In addition to other functions, digital planimeters can be scaled, making it easier to measure features on a map. The planimeter measures the distance traveled around the perimeter of the object being measured, as well as the direction. The distance traveled by the planimeter parallel to its axis is not measured. These devices are used in medicine, biology, technology, and agriculture.

Theorem on properties of areas

According to the isoperimetric theorem, of all figures with the same perimeter, the circle has the largest area. If, on the contrary, we compare figures with the same area, then the circle has the smallest perimeter. The perimeter is the sum of the lengths of the sides of a geometric figure, or the line that marks the boundaries of this figure.

Geographical features with the largest area

Country: Russia, 17,098,242 square kilometers, including land and water. The second and third largest countries by area are Canada and China.

City: New York is the city with the largest area of ​​8683 square kilometers. The second largest city by area is Tokyo, occupying 6993 square kilometers. The third is Chicago, with an area of ​​5,498 square kilometers.

City Square: The largest square, covering 1 square kilometer, is located in the capital of Indonesia, Jakarta. This is Medan Merdeka Square. The second largest area, at 0.57 square kilometers, is Praça doz Girascoes in the city of Palmas, Brazil. The third largest is Tiananmen Square in China, 0.44 square kilometers.

Lake: Geographers debate whether the Caspian Sea is a lake, but if so, it is the largest lake in the world with an area of ​​371,000 square kilometers. The second largest lake by area is Lake Superior in North America. It is one of the lakes of the Great Lakes system; its area is 82,414 square kilometers. The third largest lake in Africa is Lake Victoria. It covers an area of ​​69,485 square kilometers.